Thank you for using the Support Forum. To delete the custom paper sizes you can enter the Printing preferences for the printer on the PC and then select the down arrow on the Paper field and then select other size. Select the down arrow in the output paper size and you will see your custom sizes listed near the bottom of the list. Select the one you want to delete then select the down arrow again and select delete. If this does not help please consider contacting your support centre for further assistance.
Thanks, CherylO-Xerox Community Manager
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